Persistant ankle pain

I 'hurt' my ankle in spring of 1996. I was running alongside a horse when I stepped in a rut and my left ankle turned in so severly there was a loud distinctive POP sound. There was instantly severe swelling and bruising that went all the way up to my knee. I saw a doctor in the ER and they x-rayed it and I never got a real explaination on what I did to it. I was put in an air cast for about 7-8 weeks. I had severely sprained this ankle quite a few times before and since this incident but this was the worst.

Now I have severe pain in it again. I can't move my ankle around without loud pops and grinding. If I walk on uneven terrain for any amount of time it gets so sore that I am scared to walk on it without keeping my foot sideways (pointed to the outside) so as to avoid up and down bending. Also my achillies tendon gets so incredibly sore that I can't even rub my big toe against its buddy (the toe next to it). The pain is so sharp and intense I actually yelp out in pain.

Anyone ever deal with this? What is it? I don't know what I can do about this, I do still wear my air cast on occasion but its getting to be frusterating because the pain is so sharp and severe. Help!